1. Field of the Invention
The present invention relates to a vehicle mounted knee protection airbag apparatus that can protect the knees of an occupant sitting in a vehicle.
2. Description of Related Art
As illustrated in FIGS. 1 to 4 and FIG. 7 disclosed in JP-A-8-80797, a knee protection airbag apparatus of the related art has a space for deployment and inflation of an airbag formed in front of the knees of an occupant during an operation of the airbag. The airbag apparatus includes the airbag and a front panel. The airbag is accommodated in a folded state in front of the lower limbs of the sitting occupant. The front panel is provided in front of the lower limbs of the occupant along a substantially vertical direction. The front panel includes a lower panel portion and an upper panel portion. The lower panel portion is disposed on a rear side of an accommodation portion for the airbag. The upper panel portion extends upwardly from the lower panel portion. In the airbag apparatus, when the airbag inflates, the upper panel portion of the front panel moves to the front. In the airbag apparatus, the airbag deploys and inflates in the space formed on a rear surface-side of the moving upper panel portion.
More specifically, in the airbag apparatus, the upper panel portion includes a ceiling wall portion (an upper cover) and a general portion (a movable lower cover). The ceiling wall portion is disposed above the folded airbag along a horizontal direction. The general portion extends upwardly from a rear end of the ceiling wall portion. Furthermore, a front end of the ceiling wall portion is joined to an integral hinge that is provided on an upper surface of the accommodation portion for the airbag. A notched groove is provided in the rear end of the ceiling wall portion, and the rear end of the ceiling wall portion is joined to a lower end of the general portion. A notch-grooved portion of the ceiling wall portion can be bent and inverted. A hinge portion is provided in an upper end of the general portion, and the upper end of the general portion is joined to the vehicle body via the hinge portion. In the airbag apparatus, when the airbag inflates, first, the ceiling wall portion is pushed by the airbag, and turns upwardly to the front, having the hinge portion of the front end as a turning center. The notch-grooved portion is inverted by the turning, and the general portion connected to the rear end of the ceiling wall portion also moves in a state of being connected to the ceiling wall portion. That is, the general portion moves to the front, while turning with the hinge portion of the upper end as the turning center. For this reason, a space for the deployment and inflation of the airbag is formed on a rear side of the general portion that moves to the front.
JP-A-8-80797 (refer to FIG. 6 in JP-A-8-80797) also discloses a configuration in which a locking portion is provided in the rear end of the ceiling wall portion so as to be separable from the lower end of the general portion. In the airbag apparatus having this configuration, when the airbag operates, the general portion separates from the rear end of the ceiling wall portion, and moves to the front. For this reason, the space for the deployment and inflation of the airbag is formed on the rear side of the general portion.